JP2001302222A - Ammonium polyphosphate with improved fluidity and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ammonium polyphosphate having improved fluidity without damaging flame resistance of the ammonium polyphosphate. SOLUTION: This ammonium polyphosphate having improved fluidity is obtained by mixing total 100 wt.% comprising 96-99.95 wt.% of the ammonium polyphosphate and 4-0.05 wt.% of a melamine monomer or a melamine derivative.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ammonium polyphosphate useful as a flame retardant and having improved fluidity, and a method for producing the same. More specifically, the present invention relates to an ammonium polyphosphate obtained by adding and mixing a trace amount of a melamine monomer or a melamine derivative to ammonium polyphosphate, preventing secondary aggregation of ammonium polyphosphate and improving fluidity, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, ammonium polyphosphate (hereinafter, referred to as ammonium polyphosphate) has been used.
APP is sometimes referred to as APP) because it is a white fine powder and has excellent freedom in coloring. Even when it is added to a synthetic resin, its mechanical properties are small, and it does not generate toxic halogen-based gas. It is getting attention. However, when handling the APP, there is a problem that the fluidity is poor and the powder is agglomerated and adheres to the device, making it difficult to handle.
In addition, when APP is mixed with a thermoplastic resin, there is a problem of dispersibility that it is difficult to disperse uniformly in the resin because of the fine powder. Therefore, when molding was performed using a composition in which the APP was blended with a thermoplastic resin as a flame retardant, the resulting molded article partially had a different flame retardant concentration, and thus there was a possibility that the flame retardancy would vary. .

[0003] Therefore, in order to solve the above-mentioned problems, a method of coating or microencapsulating the surface of the APP with various polymers and modifiers has been conventionally proposed. As a method of improving the fluidity, that is, the agglomeration property of APP, JP-A-3-131508 discloses a method of coating APP with a curable silicone resin. As a method for coating APP, US Pat.
No. 4,467,056 discloses a melamine / formaldehyde resin, and US Pat. No. 4,514,328 discloses an epoxy resin, which is disclosed in DE 3438096 and JP-A-61-98.
U.S. Pat. No. 722 discloses a urea resin.
JP-A-61-98719 discloses a method for improving the fluidity by microencapsulating ammonium polyphosphate with a polycarbodiimide and US Pat. No. 4,347,334 with a phenol resin.

[0004] However, all of these methods involve dispersing a coating agent in a solution together with ammonium polyphosphate, curing and coating the coating agent on the APP surface, and then removing the coating agent. The process is complicated and costly. Further, depending on the treatment method, the coating resins surrounding the APP are cured with each other, and the average particle diameter often increases due to the formation of agglomerates.

As a method not using a solution, Japanese Patent Application Laid-Open No.
No. 134455 discloses an ammonium polyphosphate containing finely divided silica surface-treated with silicone oil in order to improve fluidity and water repellency. However, when a sufficient amount of the finely divided silica is added to improve the flowability of APP, there is a problem that the flame retardancy of ammonium polyphosphate is impaired.

[0006]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to solve the above-mentioned problems. As a result, when a very small amount of a specific melamine derivative is added to and mixed with APP, the resulting ammonium polyphosphate originally has
It has been found that the fluidity is improved without impairing the flame retardancy of P, and the present invention has been completed based on this finding.
As is apparent from the above description, an object of the present invention is to provide an ammonium polyphosphate having improved fluidity without impairing the flame retardancy of the ammonium polyphosphate.

[0007]

The present invention comprises the following. (1) When the whole is 100% by weight, 96 to 99.9.
An ammonium polyphosphate having improved fluidity obtained by mixing 5% by weight of ammonium polyphosphate with 4 to 0.05% by weight of a melamine monomer or melamine derivative.

(2) The crystal form of ammonium polyphosphate is
2. The ammonium polyphosphate having improved fluidity according to the above item 1, which is a type II or a type V.

(3) The melamine derivative is a melam, melem, melon, a reaction product of melamine and formaldehyde,
3. The ammonium polyphosphate having improved fluidity according to any one of the above items 1 or 2, which is a salt of melamine and an inorganic acid or an organic acid and a mixture thereof.

(4) The ammonium polyphosphate having improved fluidity according to the above item 1, wherein the ammonium polyphosphate having improved fluidity has an angle of repose of 20 ° to 40 °.

(5) When the whole is 100% by weight, 9%
6-99.95% by weight of ammonium polyphosphate and 4-
0.05% by weight of melamine monomer or melamine derivative in air or ammonia atmosphere for 10 minutes to 3 minutes
A method for producing ammonium polyphosphate having improved fluidity, comprising mixing for a period of time.

[0012] Ammonium polyphosphate used in the present invention have the general formula _{H (nm) +2 (NH 4} ) m P n O 3n + 1 ( wherein, n 20 to 20
00, where m has a maximum value of n + 2 and m /
n is between 0.9 and 1.1) or (NH _{4) n +} 2 P
_n O _{3n + 1} (where n represents a number from 20 to 2,000), and when the value of n is sufficiently large, it approximates the formula (NH ₄ PO ₃ ) _n of metaphosphoric acid It is a compound that can be made.

The ammonium polyphosphate generally comprises I
It is known that there are crystal forms from Form to Form VI, but the crystal forms preferably used in the present invention are Form II and Form V. The spectrum data of the crystal form is obtained from Shi Wai Shen (C.
Journal of American Chemical Societ by Y. Shen et al.
y), 91, p62-67 (1969), and the Journal of Agricultural and Food Chemistry by Kjell R. Waestad et al.
istry), vol. 24, No. 2, p412-415 (1978).

The ammonium polyphosphate used in the present invention has a practical average particle diameter of 40 μm or less.
preferable. Even when the average particle size is larger than 40 μm,
Although the fluidity is improved by the method of the present invention, when the ammonium polyphosphate is used as a flame retardant for a thermoplastic resin, the dispersibility in the resin becomes poor, and good flame retardancy cannot be obtained, When molding is performed using the obtained resin, there is a possibility that the mechanical properties of the obtained molded product are reduced. Further, the ammonium polyphosphate used in the present invention is 25%.
When 90 g of water is dispersed in 90 ml of water at 10 ° C., it is preferable that the amount dissolved per hour is 1 g or less.

Ammonium polyphosphate having such properties is commercially available as Hostaflam AP-422.
(Manufactured by Clariant), FR-CROS484 (manufactured by Boudenheim), Terage S20 (manufactured by Chisso Corporation)
In addition to the above, it can also be obtained by a known method. Known methods include, for example, the addition of approximately equimolar amounts of ammonium orthophosphate and phosphorus pentoxide in the presence of gaseous ammonia and simultaneous movement of the reactants.
A method of heating to 170 to 350 ° C. can be mentioned.

In order to obtain an ammonium polyphosphate having improved fluidity according to the present invention, a melamine monomer or a melamine derivative is added to the ammonium polyphosphate.
The melamine derivative includes melam (C ₆ H ₉ N ₁₁ ), melem (C ₆ H ₉ N ₁₀ ), and 600, which are obtained by carefully heating a melamine monomer to 350 ° C. or more.
Melon (C ₁₈₎ obtained by deammonification of three molecules of melem by heating the melem above 3 ° C.
H ₁₈ N ₂₇ ). Further, a reaction product of melamine and formaldehyde, and a salt of melamine with an organic acid or an inorganic acid can also be suitably used. As the organic acid, cyanuric acid and isocyanuric acid can be suitably used,
As the inorganic acid, sulfuric acid, phosphoric acid, and pyrophosphoric acid can be suitably used. In the present invention, the melamine monomer and the melamine derivative can be used alone or as a mixture.

The ammonium polyphosphate having improved fluidity according to the present invention comprises 0.05 to 4% by weight, preferably 0.1 to 2% by weight, based on the total amount of the mixture of ammonium polyphosphate and a melamine monomer or the aforementioned melamine derivative. weight%
It can be obtained by adding, stirring and mixing. If the content is less than 0.05% by weight, the fluidity of ammonium polyphosphate may not be improved. Even if the content exceeds 4% by weight, the effect of improving the fluidity is saturated, and the effect is further improved. In some cases, the flame retardant performance of ammonium polyphosphate may be reduced.

When stirring and mixing, the mixture may be heated to a temperature lower than the decomposition or sublimation temperature of the melamine monomer or melamine derivative. In the case of heating, in order to prevent ammonia from desorbing from ammonium polyphosphate, it is preferable to ventilate ammonia and keep the inside of the heater in an ammonia atmosphere. The ammonia aeration may be slightly greater than the partial pressure of ammonia desorbed from the ammonium polyphosphate at that temperature, and the ammonia partial pressure may be as described in the aforementioned Shen et al. Equation of vapor pressure logP = 8.207-3230 / (273.1
5 + T) (where P is the vapor pressure of ammonia (mmHg) and T is the temperature (° C.)).
It may be about kPa. When it is difficult to control a small amount of flow, it may be mixed with another gas and ventilated.

The apparatus for obtaining the ammonium polyphosphate having improved fluidity of the present invention is not particularly limited as long as it can be prepared by a person skilled in the art with a view to uniform mixing, and a commercially available ball mill, V-type blender, Mixers such as ribbon blenders, screw blenders, and kneaders can be used,
Optionally, equipment with a heating device can also be used.

[0020]

EXAMPLES Examples and comparative examples will be shown below to specifically explain the present invention, but the present invention is not limited by these examples. The raw materials and evaluation method according to the present invention were performed by the following methods.

(1) Raw materials (i) Melamine: (Ucamamine: manufactured by Mitsubishi Chemical Corporation), (i)
i) Melamine cyanurate: (Melamine cyanurate MC-44
0: Nissan Chemical Industries, Ltd.), (iii) Ammonium polyphosphate 1
(Hostafram AP-422: Clariant), (iv) Ammonium polyphosphate 2 (FRCROS-484: Bodenheim), (v) Ammonium polyphosphate 3 (Terage S)
20: Chisso Corporation)

(2) Evaluation method (i) Evaluation of fluidity Using a stainless steel funnel having a funnel angle of 40 ° and a funnel hole diameter of 15 mm, the sample powder obtained in each of the examples and comparative examples was put into the funnel. The angle of repose was measured from the radius and height of the bottom of the cone formed on a horizontal plate. The smaller the value of the angle of repose, the better the fluidity. In addition, the occurrence of funnel clogging when the sample was transferred to the funnel was also examined.

EXAMPLE 1 Melamine was added to ammonium polyphosphate 1 so as to make up 1% by weight of the total, and a V-type blender was used to obtain 2% by weight.
The mixture was mixed at 5 ° C. for 1 hour to obtain a mixed ammonium polyphosphate. Using the obtained mixed-treated ammonium polyphosphate, fluidity was evaluated by the above evaluation method. The results are shown in Table 1.

Example 2 Ammonium polyphosphate 2 and melamine were added to a 5 liter internal volume kneader equipped with a heating device so as to be 0.5% by weight of the whole, and were placed in an ammonia atmosphere at 150 ° C. for 1 hour. To obtain a mixed ammonium polyphosphate. Using the obtained mixed-treated ammonium polyphosphate, fluidity was evaluated by the above evaluation method. The results are shown in Table 1.

Example 3 Ammonium polyphosphate 3, melamine cyanurate 1% by weight and melamine 2% by weight were charged into a ribbon blender equipped with a heating device, respectively, to obtain 40% by weight. The mixture was mixed at room temperature for 2 hours in the air to obtain a mixed ammonium polyphosphate. Using the obtained mixed-treated ammonium polyphosphate, fluidity was evaluated by the above evaluation method. The results are shown in Table 1.

Comparative Example 1 The angle of repose and the clogging of the funnel of ammonium polyphosphate 2 to which melamine was not added were evaluated. The results are shown in Table 1.

COMPARATIVE EXAMPLE 2 Ammonium polyphosphate 1 and melamine cyanurate were inserted into a kneader having an inner volume of 5 liters equipped with a heating device so as to be 0.03% by weight of the whole, and were placed in an air atmosphere at 40.degree. To obtain a sample. Using the obtained sample, fluidity was evaluated by the above-described evaluation method. The results are shown in Table 1.

[0028]

[Table 1]

[0029]

The ammonium polyphosphate of the present invention is an ammonium polyphosphate whose flowability and handleability are greatly improved only by adding a small amount of melamine or a melamine derivative and a mixture thereof to ammonium polyphosphate and mixing. is there. Further, the ammonium polyphosphate of the present invention has good handleability and fluidity when used as a flame retardant in a synthetic resin or the like, so that it can be uniformly dispersed in the resin, and the amount of the additive Since the amount is very small, it is possible to impart good flame retardancy without impairing the flame retardancy inherent to ammonium polyphosphate.

Claims (5)

[Claims] (1) When the total content is 100% by weight, 96 to 9
9.95% by weight of ammonium polyphosphate and 4 to 0.0
Ammonium polyphosphate with improved flowability obtained by mixing 5% by weight of a melamine monomer or melamine derivative. 2. The method of claim 2, wherein the ammonium polyphosphate is of type II or
The ammonium polyphosphate having improved fluidity according to claim 1, which is a V-type crystal type. 3. The method according to claim 1, wherein the melamine derivative is melam, melem, melon, a reaction product of melamine with formaldehyde, a salt of melamine with an inorganic or organic acid, or a mixture thereof. An ammonium polyphosphate having improved fluidity according to the above item. 4. The ammonium polyphosphate having improved fluidity according to claim 1, wherein the ammonium polyphosphate having improved fluidity has an angle of repose of 20 ° to 40 °. 5. When the total content is 100% by weight, 96-9%
9.95% by weight of ammonium polyphosphate and 4 to 0.0
A method for producing ammonium polyphosphate having improved fluidity, comprising mixing 5% by weight of a melamine monomer or a melamine derivative in an air or ammonia atmosphere for 10 minutes to 3 hours.